Screw-fastener.



UNITED sTArns PATENT OFFICE.

ALEXANDER CRAWFORD CHENOWETH, OF NEW YORK, 1\`. Y., ASSIGNOR OF ONE-HALF TO JOHN MCNAMEE, OF BROOKLYN, NEW YORK.

SCREW-FASTENER.

No. &306,691.

Specficaton of Letters Patent.

Patented'Dec. 15, mos.

Application filed August 5, 1905, Serial No. 272,917. Renewed May 12, 1908. Serial No. 432,&48.

To all whom 'it may concem:

Be it known that I, ALEXANDER Cr nw- FORD CHENOWETH, a citizen' of the United States, residing in the borough of Manhattan, New York city, county and State of' New York, have invented certain new and useful Irnprovenents in Screw-Fasteners, of which the following is such a full, clear, and exact description as 'will enable any one skilled in the art to which it appertans to make and use the same, reference being had to the accompanying drawings, forming part of this specification,

My invention relates to a device 'for looking or fastenin a-screw in its socket so as not only to male it hold fast but to prevent its working loose under vibration or Shock.

The present invention is particularly adapted for securing a screw in its soe-ket in earthenware, or composite material, such for instance as concrete or cement and the like. I have herewith illustrated the application of the invention to a railway rail fastener, and with which a concrete tie is used.

The invention consists in the various novel and peculiar arrangements and combinations of the several different part-s of the device, all as hereinafter fully described and then pointed out in the claims. 4

I have illustrated a type of my invention in the acconpanying drawings,wherein;

Figure 1 is a vertical section of a railway rail, its tie, and my improved screw fastencr applied thereto to fasten the rail to the tie,

the section being taken longitudinallv of the tie and the parts being shown with the helical coil in the lower part of the socket before it is drawn up by the screw thread on the screw numbers of reference designate like parts throughout, 1 is a rail tie made of plastic composition, for instance concrete, and provided with a vertical erforation or socket 2 within which is fixe a metallic sleeve or bushing 3 having its intcrior of a conical shape tapering from its base 4 to its upper end 5. 6

is an ordinary railway rail with the base 7 thereof resting fiatly on the tie.

The flat head 8 of the l'astening or lag screw 9 extends over upon the base 7` of the rail it being adapted to fit down upon the same in order to clamp it to the tie when the screw is screwed home. The fiat end 8 of the screw is provided at its center with a square or polygonal shaped projection 10 adapted to receive a wrench or suitable tool for turning the screw".

The thread 11 of the screw is formed sulwith the stem around which the' thread extends being of a substantially uniform diameter throughout and u to the place where the screw begins to sudd anly taper to form the ginlet. end at its point. The diameter of the screw thread neasurecl from the point of the thread is practically the same as the upper end of the interier of the conical sleeve 3 at the point 5, so that the screw may be inserted within the small end of the sleeve, as indicated in the drawings. within the tube or sleeve 3 is placed a helical coil 12 made of a suitable resilient steel wire and having the turns of the coil of uniforn internal diameter throughout, and adapted to fit the thread 11 of the screw. The external diameter of' the coil 12 when screwcd on to the thread 11 is lz'rger than the interier diameter of the upper and small end of the sleeve or tube 3 but smaller than the lower end of such part and into which lower end the coil is introduced.

Before the screw is inserted in the socket or tube the coil 12 lies in the lower part thereof in position to be readily cngaged by the end ot'- the screw thread as the screw is inserted, so that by turning the screw in the proper direction the threads thereof'screw into the thread constituted by the loose coil 12 which is movable endwise in its socket. As the turning of the screw continues, the coil is fed up on the screw towards its head and this continues until the upper end of the coil finally is wcdged in the upper end of the tapering socket or tube between the same and the screw so tightly as to prevent further turning of the screw. Under this condition the screw is sccurely fastened within the socket by means of its thread engagng the coil in the manner described, and the coil in turn enggng the fixed abutment constituted by the walls of the tapering socket or tuba peculiar cooperation of these parts serves not only to hold the screw tightly -m position when it is screwed home, but the action of the spring col 12 operate, to pre- "vent any jar or vbration of the parts from 'causing the screw to unscrew or work loose.

` As the coil 12 is forced by the screw action into its final position, the turns in the col find. a close and com lete contactwith the coperating threads o the screw and this intimacy binds the col upon the screw threads,

` each turn of the coil having its own individua-l ad'ust'ment relatively to the other turns,

i with t e result that' the screw is locked so se- .curely within the socket that in order to release it considerable force has to be applied to the screw to unscrew the same'.

In the modification shown in Fi 4, the screw 9 has an ordinary hexagonal head S .with which is used a plate or clip 13 having a perforation 14 through which the shank of the screw extends and which plate' is adapted to fit over upon the rail base 7 to clamp the same to the' tie, a Washer 15 being used be inventioi is employe'd in con socket and may be moved endwise therein on its aXis but at the same` time is confined therein so that it cannot be dislodged from its place. v

Having thus described my invention what I claim and des'ire to secure by Letters Pat: ent is: u 1. A fastening device comprising a socket,

.a coil of less length thanthe socket, the adjacent surfaces ofthe col and socket being relatively tapered, and ala screw of a length to extendinto the soclet to engage the col and draw'itoutwardly whereby the pa'rts will be wedged into looking engagement. v

2. 'A fastening device coniprising a socket hat/tinga taperng bore,. a coil of less length than 'the socket and located in'its inner wider portion, and a lag screw of a length to eXtend into thesocket to engage the col and draw it outwardly whereby the parts will be wedged into 'looking enga ement.

In testimony w ereof, my hand in the' presence of two subscribing witnesses. g

ALEXANDER CRAWFORI) CHllNOWETH.

VVitnesses:

C'. J. IIEERMANCE, A. M. HAYES;

I have hereunto set- 

